print('======开始下载=====')
import time
for i in range(0,51):
    time.sleep(0.1)
    a = '-'*i
    b = '*'*(50-i)
    print(f"\r{i*2}{a}{b}",end='')
print()
print('======结束下载======')


# print('='*25+'start'+'='*25)
# sign = 50
# for i in range(51):
#     com = '*'*i
#     inc =